He was best known for his tenure as keeper of Mary, Queen of Scots between 1568 and 1585, his marriage to his second wife Elizabeth Talbot (Bess of Hardwick), as well as his surviving collection of written work.

In September the household was back again at Tutbury, where an additional guard or spy, temporarily joined the family in the person of Henry Hastings, 3rd Earl of Huntingdon.

Cecil and Mildmay visited Chatsworth in October, and agreed on Mary's removal to Sheffield Castle (Shrewsbury's principal seat), which took place shortly afterwards.

Elizabeth Shrewsbury, "Bess," commemorated her new initials in magnificent style: her house at Hardwick is topped with a balustrade within which the scrolling letters ES appear four times.

Barber bought wine, vinegar, damask and diaper linen for napkins, silk, canvas, caged live quails, and sugar confitures, which he delivered to the earl in London.

For this and other reasons (such as disputes over property distribution) his marriage with Bess of Hardwick, while initially successful, became rocky, and began to deteriorate around 1583, as detailed by surviving letters between the two.

[1][3] Slowly but increasingly declining health (rheumatism) caused chronic pain, and money issues that inevitably came about during his time as keeper of the Queen of Scots, made him additionally caustic.

For example, an 1875 article in the Sheffield Independent Press declared his handwriting "the despair of all transcribers" (a view still held by scholars and paleographers), which is worsened by the non-standard spelling of the time.

He is also a recurring character in Friedrich Schiller's play Mary Stuart (as Lord Shrewsbury) and in the tragic opera inspired by it, Gaetano Donizetti's Maria Stuarda (as Giorgo Talbot).